Numerous machines and tools exist for shaving the insulation jacket from electrical cable. The machinery tends to be relatively complex and is adapted for high speed, high volume operation. On the other hand, other tools have been developed which are less automated or in many instances are operated entirely manually. U.S. Pat. Nos. 3,204,495, 3,572,189, 3,659,483, 3,969,818, 3,978,582, and 4,449,298 are illustrative of various insulation-removing tools of varying complexity and suitable in most instances for hand operation. U.S. Pat. Nos. 3,548,691 and 3,620,104 are illustrative of other manually-operated, insulation-stripping tools of possibly less complexity than those of the aforementioned group. Still further, U.S. Pat. Nos. 3,304,605 and 3,548,690 are illustrative of simple manually-operated insulation-removing tools. In most instances, it is required that the tool be capable of quickly and efficiently removing the insulation from the cable without damaging the conductor.
U.S. Pat. No. 3,304,605 describes a simple tubular device having several slots of varying depth in which a manually held cutting blade may be selectively positioned. The U.S. Pat. No. 3,548,690 discloses a simple manually-operated tool having a blade affixed thereto.
In most or all of the aforementioned patents, the cable undergoing insulation removal has a single or multi-stranded center conductor and a surrounding jacket of insulation. In some instances the electrical cable may be of a coaxial type and include an additional dielectric layer and possibly also a braided shield. In those instances, there has been little or no emphasis placed on the angular disposition of the cutting blade relative to the axis of the cable. In certain instances, such as that disclosed in U.S. Pat. No. 3,572,189, the cutting edge is intended to be disposed at an angle other than 90.degree. to the longitudinal axis of the conductor cable so as to provide a screw-feed action.
Certain types of electrical cable and specifically ignition cable, include a helical winding of resistance wire disposed about a central core to provide the electrically conductive path. An example of such wire-wound ignition cable is disclosed in U.S. Pat. No. 3,518,606 wherein a resistance wire is helically wound about a fibrous insulating core to form a wire-wound core. That wire-wound core is then encased in a conventional insulating coating. Various thin binding layers may also exist about the central fibrous core and about the wire winding. A thin releasing layer may also be interposed between the insulation and the wire winding. Typically, a particular manufacturer of wire-wound ignition cable will provide the wire winding in a single direction, either clockwise or counterclockwise as viewed from the end.
To prepare the ignition cable for use with an associated terminal, it is generally necessary to remove the insulation to a depth which exposes the wire-wound core. The wire-wound core is then crimped or otherwise secured in electrically-conducting engagement with the terminal, as illustrated in U.S. Pat. No. 3,518,606. In the mass production of such wire-wound ignition cables with terminals, the insulation has typically been removed from the wire-wound core by a scissor-like or guillotine-like stripper which removes the desired length of insulation with a single cut.
While the aforementioned technique for removing insulation from wire-wound ignition cables is suited for the mass production of ignition cables with terminals, numerous individuals find it necessary and/or desirable to prepare wire-wound ignition cable for joining with an appropriate terminal. Such persons typically include the do-it-yourselfer, the hobbyist, and the racing enthusiast, amongst others. In such instance, care must be taken to preserve the integrity of the resistance wire winding as the insulation is being cut and removed from the cable. The integrity of the resistance wire winding is essential for good electrical connection with the terminal.